In 3GPP, a “Fast Dormancy function” is specified for the purpose of saving the batteries of mobile stations UE (see Non-patent Document 1).
With this “Fast Dormancy function,” each mobile station UE is configured to transmit “SIGNALLING CONNECTION RELEASE INDICATION” to its radio access network (radio base station eNB) when detecting that there is no more data to be transmitted so that the mobile station UE can immediately transition to a “Preservation state.”
Here, the radio access network (radio base station eNB) can control the interval of retransmission of the “SIGNALLING CONNECTION RELEASE INDICATION” from the mobile station UE by notifying the mobile station UE of the value of a timer T323.